The present invention relates to a method and system for delivering a pressurized fluid, such as hydrogen or another compressed gas, to a receiving tank, such as a vehicle fuel tank, and in particular the invention relates to a self-powered mobile fueling station for delivering a fuel (e.g., hydrogen) at pressures of 5,000 psig or greater to fuel tanks of vehicles, such as hydrogen-powered vehicles.
Although the invention is discussed herein with regard to delivery of pressurized hydrogen gas to fuel tanks of hydrogen-powered vehicles, persons skilled in the art will recognize that the invention has other applications. For example, it may be used to deliver other pressurized fluids which may or may not be used as fuels, and the pressurized fluids may be delivered to various types of receiving tanks other than vehicle fuel tanks.
With the increasing interest in clean and efficient fuels, automobile manufacturers are designing and manufacturing hydrogen-powered vehicles that are powered by fuel cells or hydrogen internal combustion engines. Hydrogen is being tested in these vehicles and has the potential to be the fuel of choice in the future.
These hydrogen-powered vehicles are in the development stage and manufacturers are performing extensive tests to improve the vehicles and related technologies. Since there is not an established hydrogen fueling infrastructure in place, some manufacturers are installing fixed hydrogen fueling stations at test sites and elsewhere. Testing is taking place throughout North America without sufficient capability to fuel the test vehicles away from the fixed hydrogen fueling stations.
Hydrogen-powered vehicles are also being demonstrated and promoted at public events to increase consumer awareness and interest. These events are taking place at many locations where hydrogen fueling is needed but is not available. Currently, hydrogen is delivered to these events in the form of liquid or as a cylinder product.
BX cylinders, individually or in packs, are typically used to provide hydrogen to customers. However, these cylinders are very heavy and difficult (expensive) to transport.
In view of the above, there is a need for mobile hydrogen fueling stations to fuel test vehicles and demonstration vehicles at public events. Mobile hydrogen fueling stations also could be used for maintaining small fleets of hydrogen-powered vehicles, providing fuel for emergency roadside assistance, and for fueling stationary fuel cells or hydrogen-powered facilities at remote sites.
Powertech Labs and Dynatek, Inc. have offered for sale a mobile fueling station that is believed to have a supply pressure of 3,600 psig.
There exists a void in the availability of fuel for hydrogen-powered vehicles. Government and industry demonstration projects are hampered by the inability to fuel the prototype vehicles being tested and demonstrated.
In view of the current needs of industry and government programs, a mobile hydrogen fueling station is needed. Preferably, such a station should be a self-contained, self-powered, mobile fueling station capable of delivering high pressure gas (e.g., at pressures of 5,000 psig or more) in an optimal manner (e.g., minimal fueling time and maximum usage of the fuel carried by the mobile fueling station so as to minimize the need to refill the station).
As used herein, the term “self-contained” means that the power needed to actuate valves, deliver compressed gas at maximum pressure and at maximum rates, provide communications between the fueling station and a vehicle to be filled, and provide communications between the fueling station and a remote monitor is inherent in the fueling station. The term “self-powered” means that no external electric power or other external utilities are needed to operate the fueling functions of the mobile fueling station.
Although the prior art includes various types of mobile fueling stations, none of these stations satisfy the current needs. For example, U.S. Pat. Nos. 5,983,962 and 3,257,031 each disclose a mobile fueling station. However, these patents do not teach how to deliver high-pressure hydrogen in an optimal manner.
Other patents and publications also disclose mobile delivery stations for storing and dispensing fuel, but these stations are not self-powered and are not designed to deliver high-pressure hydrogen in an optimal manner. See for example, U.S. Pat. Nos. 5,887,567 and 5,682,750. See also U.S. Patent Application No. 2002/0046773 and International Publication WO 98/52677.
U.S. Pat. No. 5,596,501 discloses a system for dispensing fuel at remote locations and a method of operating same. However, it does not teach a mobile self-contained delivery station for delivering high-pressure hydrogen in an optimal manner.
The present invention teaches delivery of high-pressure hydrogen in a cascading manner to optimize fueling time. Although the prior art does disclose cascading (e.g., U.S. Pat. Nos. 5,673,735 and 5,810,058), it does not disclose cascading delivery in an optimal manner (e.g., to provide an optimal rate of fill) for use in a self-powered, self-contained mobile hydrogen fueling station.
U.S. Patent Application No. 2002/0014277 discloses an apparatus and method for filling a tank with hydrogen gas. However, it does not address the problems involved with filling tanks or storage vessels of various sizes.
It is desired to have an improved method and system for delivering a pressurized fluid, such as hydrogen gas, to a receiving tank, such as a vehicle fuel tank.
It is further desired to have a method and system to allow for the fueling of hydrogen-powered vehicles in areas where there is no hydrogen infrastructure (pipeline, plants, filling stations, etc.).
It is still further desired to have a self-contained mobile fueling station which can be deployed anywhere and provide fuel, such as hydrogen, to vehicle demonstration projects on an efficient, economical basis.
It is still further desired to have an automatic method and system to safely store and dispense hydrogen gas at different pressures, making it possible to fuel a vehicle rated for 5,000 psig or more without the use of a compressor.
It is still further desired to have a self-powered mobile hydrogen fueling station to support hydrogen demonstration projects and small hydrogen-powered vehicle fleets without the use of external electric power or other external utilities.
It is still further desired to have a self-powered mobile hydrogen fueling station which also may be used to provide emergency roadside assistance to hydrogen-powered vehicles and/or to stationary fuel cells or hydrogen-powered facilities at remote locations.
It is still further desired to have an improved method and system for controlling the rate of delivery of a pressurized fluid, such as hydrogen gas, to a receiving tank, such as a vehicle fuel tank.
It also is desired to have a method and system for delivering a pressurized fluid, such as a hydrogen fuel, at a controlled rate of delivery to receiving tanks of various sizes, such as vehicle fuel tanks, which afford better performance than the prior art, and which also overcome many of the difficulties and disadvantages of the prior art to provide better and more advantageous results.